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2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104Thomas Gleixner
Based on 1 normalized pattern(s): this sctp implementation is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 or at your option any later version this sctp implementation is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with gnu cc see the file copying if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 42 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190523091649.683323110@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-22sctp: don't compare hb_timer expire date before starting itMaciej Kwiecien
hb_timer might not start at all for a particular transport because its start is conditional. In a result a node is not sending heartbeats. Function sctp_transport_reset_hb_timer has two roles: - initial start of hb_timer for a given transport, - update expire date of hb_timer for a given transport. The function is optimized to update timer's expire only if it is before a new calculated one but this comparison is invalid for a timer which has not yet started. Such a timer has expire == 0 and if a new expire value is bigger than (MAX_JIFFIES / 2 + 2) then "time_before" macro will fail and timer will not start resulting in no heartbeat packets send by the node. This was found when association was initialized within first 5 mins after system boot due to jiffies init value which is near to MAX_JIFFIES. Test kernel version: 4.9.154 (ARCH=arm) hb_timer.expire = 0; //initialized, not started timer new_expire = MAX_JIFFIES / 2 + 2; //or more time_before(hb_timer.expire, new_expire) == false Fixes: ba6f5e33bdbb ("sctp: avoid refreshing heartbeat timer too often") Reported-by: Marcin Stojek <marcin.stojek@nokia.com> Tested-by: Marcin Stojek <marcin.stojek@nokia.com> Signed-off-by: Maciej Kwiecien <maciej.kwiecien@nokia.com> Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-20sctp: update dst pmtu with the correct daddrXin Long
When processing pmtu update from an icmp packet, it calls .update_pmtu with sk instead of skb in sctp_transport_update_pmtu. However for sctp, the daddr in the transport might be different from inet_sock->inet_daddr or sk->sk_v6_daddr, which is used to update or create the route cache. The incorrect daddr will cause a different route cache created for the path. So before calling .update_pmtu, inet_sock->inet_daddr/sk->sk_v6_daddr should be updated with the daddr in the transport, and update it back after it's done. The issue has existed since route exceptions introduction. Fixes: 4895c771c7f0 ("ipv4: Add FIB nexthop exceptions.") Reported-by: ian.periam@dialogic.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-04sctp: fix the issue that pathmtu may be set lower than MINSEGMENTXin Long
After commit b6c5734db070 ("sctp: fix the handling of ICMP Frag Needed for too small MTUs"), sctp_transport_update_pmtu would refetch pathmtu from the dst and set it to transport's pathmtu without any check. The new pathmtu may be lower than MINSEGMENT if the dst is obsolete and updated by .get_dst() in sctp_transport_update_pmtu. In this case, it could have a smaller MTU as well, and thus we should validate it against MINSEGMENT instead. Syzbot reported a warning in sctp_mtu_payload caused by this. This patch refetches the pathmtu by calling sctp_dst_mtu where it does the check against MINSEGMENT. v1->v2: - refetch the pathmtu by calling sctp_dst_mtu instead as Marcelo's suggestion. Fixes: b6c5734db070 ("sctp: fix the handling of ICMP Frag Needed for too small MTUs") Reported-by: syzbot+f0d9d7cba052f9344b03@syzkaller.appspotmail.com Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-05sctp: not allow transport timeout value less than HZ/5 for hb_timerXin Long
syzbot reported a rcu_sched self-detected stall on CPU which is caused by too small value set on rto_min with SCTP_RTOINFO sockopt. With this value, hb_timer will get stuck there, as in its timer handler it starts this timer again with this value, then goes to the timer handler again. This problem is there since very beginning, and thanks to Eric for the reproducer shared from a syzbot mail. This patch fixes it by not allowing sctp_transport_timeout to return a smaller value than HZ/5 for hb_timer, which is based on TCP's min rto. Note that it doesn't fix this issue by limiting rto_min, as some users are still using small rto and no proper value was found for it yet. Reported-by: syzbot+3dcd59a1f907245f891f@syzkaller.appspotmail.com Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27sctp: re-use sctp_transport_pmtu in sctp_transport_routeMarcelo Ricardo Leitner
sctp_transport_route currently is very similar to sctp_transport_pmtu plus a few other bits. This patch reuses sctp_transport_pmtu in sctp_transport_route and removes the duplicated code. Also, as all calls to sctp_transport_route were forcing the dst release before calling it, let's just include such release too. Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27sctp: introduce sctp_dst_mtuMarcelo Ricardo Leitner
Which makes sure that the MTU respects the minimum value of SCTP_DEFAULT_MINSEGMENT and that it is correctly aligned. Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27sctp: move transport pathmtu calc away of sctp_assoc_add_peerMarcelo Ricardo Leitner
There was only one case that sctp_assoc_add_peer couldn't handle, which is when SPP_PMTUD_DISABLE is set and pathmtu not initialized. So add this situation to sctp_transport_route and reuse what was already in there. Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-08sctp: fix the handling of ICMP Frag Needed for too small MTUsMarcelo Ricardo Leitner
syzbot reported a hang involving SCTP, on which it kept flooding dmesg with the message: [ 246.742374] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default minimum of 512 That happened because whenever SCTP hits an ICMP Frag Needed, it tries to adjust to the new MTU and triggers an immediate retransmission. But it didn't consider the fact that MTUs smaller than the SCTP minimum MTU allowed (512) would not cause the PMTU to change, and issued the retransmission anyway (thus leading to another ICMP Frag Needed, and so on). As IPv4 (ip_rt_min_pmtu=556) and IPv6 (IPV6_MIN_MTU=1280) minimum MTU are higher than that, sctp_transport_update_pmtu() is changed to re-fetch the PMTU that got set after our request, and with that, detect if there was an actual change or not. The fix, thus, skips the immediate retransmission if the received ICMP resulted in no change, in the hope that SCTP will select another path. Note: The value being used for the minimum MTU (512, SCTP_DEFAULT_MINSEGMENT) is not right and instead it should be (576, SCTP_MIN_PMTU), but such change belongs to another patch. Changes from v1: - do not disable PMTU discovery, in the light of commit 06ad391919b2 ("[SCTP] Don't disable PMTU discovery when mtu is small") and as suggested by Xin Long. - changed the way to break the rtx loop by detecting if the icmp resulted in a change or not Changes from v2: none See-also: https://lkml.org/lkml/2017/12/22/811 Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-25net: sctp: Convert timers to use timer_setup()Kees Cook
In preparation for unconditionally passing the struct timer_list pointer to all timer callbacks, switch to using the new timer_setup() and from_timer() to pass the timer pointer explicitly. Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: linux-sctp@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-06sctp: remove the typedef sctp_lower_cwnd_tXin Long
This patch is to remove the typedef sctp_lower_cwnd_t, and replace with enum sctp_lower_cwnd in the places where it's using this typedef. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-04net, sctp: convert sctp_transport.refcnt from atomic_t to refcount_tReshetova, Elena
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-25sctp: adjust ssthresh when transport is idleMarcelo Ricardo Leitner
RFC 4960 Errata 3.27 identifies that ssthresh should be adjusted to cwnd because otherwise it could cause the transport to lock into congestion avoidance phase specially if ssthresh was previously reduced by some packet drop, leading to poor performance. The Errata says to adjust ssthresh to cwnd only once, though the same goal is achieved by updating it every time we update cwnd too. The caveat is that we could take longer to get back up to speed but that should be compensated by the fact that we don't adjust on RTO basis (as RFC says) but based on Heartbeats, which are usually way longer. See-also: https://tools.ietf.org/html/draft-ietf-tsvwg-rfc4960-errata-01#section-3.27 Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-25sctp: adjust cwnd increase in Congestion Avoidance phaseMarcelo Ricardo Leitner
RFC4960 Errata 3.26 identified that at the same time RFC4960 states that cwnd should never grow more than 1*MTU per RTT, Section 7.2.2 was underspecified and as described could allow increasing cwnd more than that. This patch updates it so partial_bytes_acked is maxed to cwnd if flight_size doesn't reach cwnd, protecting it from such case. See-also: https://tools.ietf.org/html/draft-ietf-tsvwg-rfc4960-errata-01#section-3.26 Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-25sctp: allow increasing cwnd regardless of ctsn moving or notMarcelo Ricardo Leitner
As per RFC4960 Errata 3.22, this condition is not needed anymore as it could cause the partial_bytes_acked to not consider the TSNs acked in the Gap Ack Blocks although they were received by the peer successfully. This patch thus drops the check for new Cumulative TSN Ack Point, leaving just the flight_size < cwnd one. See-also: https://tools.ietf.org/html/draft-ietf-tsvwg-rfc4960-errata-01#section-3.22 Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-25sctp: update order of adjustments of partial_bytes_acked and cwndMarcelo Ricardo Leitner
RFC4960 Errata 3.12 says RFC4960 is unclear about the order of adjustments applied to partial_bytes_acked and cwnd in the congestion avoidance phase, and that the actual order should be: partial_bytes_acked is reset to (partial_bytes_acked - cwnd). Next, cwnd is increased by MTU. We were first increasing cwnd, and then subtracting the new value pba, which leads to a different result as pba is smaller than what it should and could cause cwnd to not grow as much. See-also: https://tools.ietf.org/html/draft-ietf-tsvwg-rfc4960-errata-01#section-3.12 Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-05sctp: get sock from transport in sctp_transport_update_pmtuXin Long
This patch is almost to revert commit 02f3d4ce9e81 ("sctp: Adjust PMTU updates to accomodate route invalidation."). As t->asoc can't be NULL in sctp_transport_update_pmtu, it could get sk from asoc, and no need to pass sk into that function. It is also to remove some duplicated codes from that function. Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-27scripts/spelling.txt: add "varible" pattern and fix typo instancesMasahiro Yamada
Fix typos and add the following to the scripts/spelling.txt: varible||variable While we are here, tidy up the comment blocks that fit in a single line for drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c and net/sctp/transport.c. Link: http://lkml.kernel.org/r/1481573103-11329-11-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-07sctp: add dst_pending_confirm flagJulian Anastasov
Add new transport flag to allow sockets to confirm neighbour. When same struct dst_entry can be used for many different neighbours we can not use it for pending confirmations. The flag is propagated from transport to every packet. It is reset when cached dst is reset. Reported-by: YueHaibing <yuehaibing@huawei.com> Fixes: 5110effee8fd ("net: Do delayed neigh confirmation.") Fixes: f2bb4bedf35d ("ipv4: Cache output routes in fib_info nexthops.") Signed-off-by: Julian Anastasov <ja@ssi.bg> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-18sctp: add stream reconf timerXin Long
This patch is to add a per transport timer based on sctp timer frame for stream reconf chunk retransmission. It would start after sending a reconf request chunk, and stop after receiving the response chunk. If the timer expires, besides retransmitting the reconf request chunk, it would also do the same thing with data RTO timer. like to increase the appropriate error counts, and perform threshold management, possibly destroying the asoc if sctp retransmission thresholds are exceeded, just as section 5.1.1 describes. This patch is also to add asoc strreset_chunk, it is used to save the reconf request chunk, so that it can be retransmitted, and to check if the response is really for this request by comparing the information inside with the response chunk as well. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-25ktime: Cleanup ktime_set() usageThomas Gleixner
ktime_set(S,N) was required for the timespec storage type and is still useful for situations where a Seconds and Nanoseconds part of a time value needs to be converted. For anything where the Seconds argument is 0, this is pointless and can be replaced with a simple assignment. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
2016-09-22sctp: rename WORD_TRUNC/ROUND macrosMarcelo Ricardo Leitner
To something more meaningful these days, specially because this is working on packet headers or lengths and which are not tied to any CPU arch but to the protocol itself. So, WORD_TRUNC becomes SCTP_TRUNC4 and WORD_ROUND becomes SCTP_PAD4. Reported-by: David Laight <David.Laight@ACULAB.COM> Reported-by: David Miller <davem@davemloft.net> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-10sctp: avoid refreshing heartbeat timer too oftenMarcelo Ricardo Leitner
Currently on high rate SCTP streams the heartbeat timer refresh can consume quite a lot of resources as timer updates are costly and it contains a random factor, which a) is also costly and b) invalidates mod_timer() optimization for not editing a timer to the same value. It may even cause the timer to be slightly advanced, for no good reason. As suggested by David Laight this patch now removes this timer update from hot path by leaving the timer on and re-evaluating upon its expiration if the heartbeat is still needed or not, similarly to what is done for TCP. If it's not needed anymore the timer is re-scheduled to the new timeout, considering the time already elapsed. For this, we now record the last tx timestamp per transport, updated in the same spots as hb timer was restarted on tx. Also split up sctp_transport_reset_timers into sctp_transport_reset_t3_rtx and sctp_transport_reset_hb_timer, so we can re-arm T3 without re-arming the heartbeat one. On loopback with MTU of 65535 and data chunks with 1636, so that we have a considerable amount of chunks without stressing system calls, netperf -t SCTP_STREAM -l 30, perf looked like this before: Samples: 103K of event 'cpu-clock', Event count (approx.): 25833000000 Overhead Command Shared Object Symbol + 6,15% netperf [kernel.vmlinux] [k] copy_user_enhanced_fast_string - 5,43% netperf [kernel.vmlinux] [k] _raw_write_unlock_irqrestore - _raw_write_unlock_irqrestore - 96,54% _raw_spin_unlock_irqrestore - 36,14% mod_timer + 97,24% sctp_transport_reset_timers + 2,76% sctp_do_sm + 33,65% __wake_up_sync_key + 28,77% sctp_ulpq_tail_event + 1,40% del_timer - 1,84% mod_timer + 99,03% sctp_transport_reset_timers + 0,97% sctp_do_sm + 1,50% sctp_ulpq_tail_event And after this patch, now with netperf -l 60: Samples: 230K of event 'cpu-clock', Event count (approx.): 57707250000 Overhead Command Shared Object Symbol + 5,65% netperf [kernel.vmlinux] [k] memcpy_erms + 5,59% netperf [kernel.vmlinux] [k] copy_user_enhanced_fast_string - 5,05% netperf [kernel.vmlinux] [k] _raw_spin_unlock_irqrestore - _raw_spin_unlock_irqrestore + 49,89% __wake_up_sync_key + 45,68% sctp_ulpq_tail_event - 2,85% mod_timer + 76,51% sctp_transport_reset_t3_rtx + 23,49% sctp_do_sm + 1,55% del_timer + 2,50% netperf [sctp] [k] sctp_datamsg_from_user + 2,26% netperf [sctp] [k] sctp_sendmsg Throughput-wise, from 6800mbps without the patch to 7050mbps with it, ~3.7%. Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-20sctp: align MTU to a wordMarcelo Ricardo Leitner
SCTP is a protocol that is aligned to a word (4 bytes). Thus using bare MTU can sometimes return values that are not aligned, like for loopback, which is 65536 but ipv4_mtu() limits that to 65535. This mis-alignment will cause the last non-aligned bytes to never be used and can cause issues with congestion control. So it's better to just consider a lower MTU and keep congestion control calcs saner as they are based on PMTU. Same applies to icmp frag needed messages, which is also fixed by this patch. One other effect of this is the inability to send MTU-sized packet without queueing or fragmentation and without hitting Nagle. As the check performed at sctp_packet_can_append_data(): if (chunk->skb->len + q->out_qlen >= transport->pathmtu - packet->overhead) /* Enough data queued to fill a packet */ return SCTP_XMIT_OK; with the above example of MTU, if there are no other messages queued, one cannot send a packet that just fits one packet (65532 bytes) and without causing DATA chunk fragmentation or a delay. v2: - Added WORD_TRUNC macro Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-13sctp: fix the transports round robin issue when init is retransmittedXin Long
prior to this patch, at the beginning if we have two paths in one assoc, they may have the same params other than the last_time_heard, it will try the paths like this: 1st cycle try trans1 fail. then trans2 is selected.(cause it's last_time_heard is after trans1). 2nd cycle: try trans2 fail then trans2 is selected.(cause it's last_time_heard is after trans1). 3rd cycle: try trans2 fail then trans2 is selected.(cause it's last_time_heard is after trans1). .... trans1 will never have change to be selected, which is not what we expect. we should keeping round robin all the paths if they are just added at the beginning. So at first every tranport's last_time_heard should be initialized 0, so that we ensure they have the same value at the beginning, only by this, all the transports could get equal chance to be selected. Then for sctp_trans_elect_best, it should return the trans_next one when *trans == *trans_next, so that we can try next if it fails, but now it always return trans. so we can fix it by exchanging these two params when we calls sctp_trans_elect_tie(). Fixes: 4c47af4d5eb2 ('net: sctp: rework multihoming retransmission path selection to rfc4960') Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-28sctp: remove the dead field of sctp_transportXin Long
After we use refcnt to check if transport is alive, the dead can be removed from sctp_transport. The traversal of transport_addr_list in procfs dump is using list_for_each_entry_rcu, no need to check if it has been freed. sctp_generate_t3_rtx_event and sctp_generate_heartbeat_event is protected by sock lock, it's not necessary to check dead, either. also, the timers are cancelled when sctp_transport_free() is called, that it doesn't wait for refcnt to reach 0 to cancel them. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-28sctp: fix the transport dead race check by using atomic_add_unless on refcntXin Long
Now when __sctp_lookup_association is running in BH, it will try to check if t->dead is set, but meanwhile other CPUs may be freeing this transport and this assoc and if it happens that __sctp_lookup_association checked t->dead a bit too early, it may think that the association is still good while it was already freed. So we fix this race by using atomic_add_unless in sctp_transport_hold. After we get one transport from hashtable, we will hold it only when this transport's refcnt is not 0, so that we can make sure t->asoc cannot be freed before we hold the asoc again. Note that sctp association is not freed using RCU so we can't use atomic_add_unless() with it as it may just be too late for that either. Fixes: 4f0087812648 ("sctp: apply rhashtable api to send/recv path") Reported-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-09remove abs64()Andrew Morton
Switch everything to the new and more capable implementation of abs(). Mainly to give the new abs() a bit of a workout. Cc: Michal Nazarewicz <mina86@mina86.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-31sctp: Fixup v4mapped behaviour to comply with Sock APIJason Gunthorpe
The SCTP socket extensions API document describes the v4mapping option as follows: 8.1.15. Set/Clear IPv4 Mapped Addresses (SCTP_I_WANT_MAPPED_V4_ADDR) This socket option is a Boolean flag which turns on or off the mapping of IPv4 addresses. If this option is turned on, then IPv4 addresses will be mapped to V6 representation. If this option is turned off, then no mapping will be done of V4 addresses and a user will receive both PF_INET6 and PF_INET type addresses on the socket. See [RFC3542] for more details on mapped V6 addresses. This description isn't really in line with what the code does though. Introduce addr_to_user (renamed addr_v4map), which should be called before any sockaddr is passed back to user space. The new function places the sockaddr into the correct format depending on the SCTP_I_WANT_MAPPED_V4_ADDR option. Audit all places that touched v4mapped and either sanely construct a v4 or v6 address then call addr_to_user, or drop the unnecessary v4mapped check entirely. Audit all places that call addr_to_user and verify they are on a sycall return path. Add a custom getname that formats the address properly. Several bugs are addressed: - SCTP_I_WANT_MAPPED_V4_ADDR=0 often returned garbage for addresses to user space - The addr_len returned from recvmsg was not correct when returning AF_INET on a v6 socket - flowlabel and scope_id were not zerod when promoting a v4 to v6 - Some syscalls like bind and connect behaved differently depending on v4mapped Tested bind, getpeername, getsockname, connect, and recvmsg for proper behaviour in v4mapped = 1 and 0 cases. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Tested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-02net: sctp: improve timer slack calculation for transport HBsDaniel Borkmann
RFC4960, section 8.3 says: On an idle destination address that is allowed to heartbeat, it is recommended that a HEARTBEAT chunk is sent once per RTO of that destination address plus the protocol parameter 'HB.interval', with jittering of +/- 50% of the RTO value, and exponential backoff of the RTO if the previous HEARTBEAT is unanswered. Currently, we calculate jitter via sctp_jitter() function first, and then add its result to the current RTO for the new timeout: TMO = RTO + (RAND() % RTO) - (RTO / 2) `------------------------^-=> sctp_jitter() Instead, we can just simplify all this by directly calculating: TMO = (RTO / 2) + (RAND() % RTO) With the help of prandom_u32_max(), we don't need to open code our own global PRNG, but can instead just make use of the per CPU implementation of prandom with better quality numbers. Also, we can now spare us the conditional for divide by zero check since no div or mod operation needs to be used. Note that prandom_u32_max() won't emit the same result as a mod operation, but we really don't care here as we only want to have a random number scaled into RTO interval. Note, exponential RTO backoff is handeled elsewhere, namely in sctp_do_8_2_transport_strike(). Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-11net: sctp: migrate most recently used transport to ktimeDaniel Borkmann
Be more precise in transport path selection and use ktime helpers instead of jiffies to compare and pick the better primary and secondary recently used transports. This also avoids any side-effects during a possible roll-over, and could lead to better path decision-making. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13net: remove unnecessary return'sstephen hemminger
One of my pet coding style peeves is the practice of adding extra return; at the end of function. Kill several instances of this in network code. I suppose some coccinelle wizardy could do this automatically. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Merge 'net' into 'net-next' to get the AF_PACKET bug fix that Daniel's direct transmit changes depend upon. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06sctp: Fix FSF address in file headersJeff Kirsher
Several files refer to an old address for the Free Software Foundation in the file header comment. Resolve by replacing the address with the URL <http://www.gnu.org/licenses/> so that we do not have to keep updating the header comments anytime the address changes. CC: Vlad Yasevich <vyasevich@gmail.com> CC: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05sctp: disable max_burst when the max_burst is 0wangweidong
As Michael pointed out that when max_burst is 0, it just disable max_burst. It declared in rfc6458#section-8.1.24. so add the check in sctp_transport_burst_limited, when it 0, just do nothing. Reviewed-by: Daniel Borkmann <dborkman@redhat.com> Suggested-by: Vlad Yasevich <vyasevich@gmail.com> Suggested-by: Michael Tuexen <Michael.Tuexen@lurchi.franken.de> Signed-off-by: Wang Weidong <wangweidong1@huawei.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2013-08-12net: sctp: sctp_transport_destroy{, _rcu}: fix potential pointer corruptionDaniel Borkmann
Probably this one is quite unlikely to be triggered, but it's more safe to do the call_rcu() at the end after we have dropped the reference on the asoc and freed sctp packet chunks. The reason why is because in sctp_transport_destroy_rcu() the transport is being kfree()'d, and if we're unlucky enough we could run into corrupted pointers. Probably that's more of theoretical nature, but it's safer to have this simple fix. Introduced by commit 8c98653f ("sctp: sctp_close: fix release of bindings for deferred call_rcu's"). I also did the 8c98653f regression test and it's fine that way. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-09net: sctp: trivial: update bug report in header commentDaniel Borkmann
With the restructuring of the lksctp.org site, we only allow bug reports through the SCTP mailing list linux-sctp@vger.kernel.org, not via SF, as SF is only used for web hosting and nothing more. While at it, also remove the obvious statement that bugs will be fixed and incooperated into the kernel. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-24net: sctp: trivial: update mailing list addressDaniel Borkmann
The SCTP mailing list address to send patches or questions to is linux-sctp@vger.kernel.org and not lksctp-developers@lists.sourceforge.net anymore. Therefore, update all occurences. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-01net: sctp: rework debugging framework to use pr_debug and friendsDaniel Borkmann
We should get rid of all own SCTP debug printk macros and use the ones that the kernel offers anyway instead. This makes the code more readable and conform to the kernel code, and offers all the features of dynamic debbuging that pr_debug() et al has, such as only turning on/off portions of debug messages at runtime through debugfs. The runtime cost of having CONFIG_DYNAMIC_DEBUG enabled, but none of the debug statements printing, is negligible [1]. If kernel debugging is completly turned off, then these statements will also compile into "empty" functions. While we're at it, we also need to change the Kconfig option as it /now/ only refers to the ifdef'ed code portions in outqueue.c that enable further debugging/tracing of SCTP transaction fields. Also, since SCTP_ASSERT code was enabled with this Kconfig option and has now been removed, we transform those code parts into WARNs resp. where appropriate BUG_ONs so that those bugs can be more easily detected as probably not many people have SCTP debugging permanently turned on. To turn on all SCTP debugging, the following steps are needed: # mount -t debugfs none /sys/kernel/debug # echo -n 'module sctp +p' > /sys/kernel/debug/dynamic_debug/control This can be done more fine-grained on a per file, per line basis and others as described in [2]. [1] https://www.kernel.org/doc/ols/2009/ols2009-pages-39-46.pdf [2] Documentation/dynamic-debug-howto.txt Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17net: sctp: get rid of t_new macro for kzallocDaniel Borkmann
t_new rather obfuscates things where everyone else is using actual function names instead of that macro, so replace it with kzalloc, which is the function t_new wraps. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-17net: sctp: sctp_transport: remove unused variableDaniel Borkmann
sctp_transport's member 'malloced' is set to 1, never evaluated and the structure is kfreed anyway. So just remove it. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-04net: remove redundant check for timer pending state before del_timerYing Xue
As in del_timer() there has already placed a timer_pending() function to check whether the timer to be deleted is pending or not, it's unnecessary to check timer pending state again before del_timer() is called. Signed-off-by: Ying Xue <ying.xue@windriver.com> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-04sctp: sctp_close: fix release of bindings for deferred call_rcu'sDaniel Borkmann
It seems due to RCU usage, i.e. within SCTP's address binding list, a, say, ``behavioral change'' was introduced which does actually not conform to the RFC anymore. In particular consider the following (fictional) scenario to demonstrate this: do: Two SOCK_SEQPACKET-style sockets are opened (S1, S2) S1 is bound to 127.0.0.1, port 1024 [server] S2 is bound to 127.0.0.1, port 1025 [client] listen(2) is invoked on S1 From S2 we call one sendmsg(2) with msg.msg_name and msg.msg_namelen parameters set to the server's address S1, S2 are closed goto do The first pass of this loop passes successful, while the second round fails during binding of S1 (address still in use). What is happening? In the first round, the initial handshake is being done, and, at the time close(2) is called on S1, a non-graceful shutdown is performed via ABORT since in S1's receive queue an unprocessed packet is present, thus stating an error condition. This can be considered as a correct behavior. During close also all bound addresses are freed, thus nothing *must* be active anymore. In reference to RFC2960: After checking the Verification Tag, the receiving endpoint shall remove the association from its record, and shall report the termination to its upper layer. (9.1 Abort of an Association) Also, no half-open states are supported, thus after an ungraceful shutdown, we leave nothing behind. However, this seems not to be happening though. In a real-world scenario, this is exactly where it breaks the lksctp-tools functional test suite, *for instance*: ./test_sockopt test_sockopt.c 1 PASS : getsockopt(SCTP_STATUS) on a socket with no assoc test_sockopt.c 2 PASS : getsockopt(SCTP_STATUS) test_sockopt.c 3 PASS : getsockopt(SCTP_STATUS) with invalid associd test_sockopt.c 4 PASS : getsockopt(SCTP_STATUS) with NULL associd test_sockopt.c 5 BROK : bind: Address already in use The underlying problem is that sctp_endpoint_destroy() hasn't been triggered yet while the next bind attempt is being done. It will be triggered eventually (but too late) by sctp_transport_destroy_rcu() after one RCU grace period: sctp_transport_destroy() sctp_transport_destroy_rcu() ----. sctp_association_put() [*] <--+--> sctp_packet_free() sctp_association_destroy() [...] sctp_endpoint_put() skb->destructor sctp_endpoint_destroy() sctp_wfree() sctp_bind_addr_free() sctp_association_put() [*] Thus, we move out the condition with sctp_association_put() as well as the sctp_packet_free() invocation and the issue can be solved. We also better free the SCTP chunks first before putting the ref of the association. With this patch, the example above (which simulates a similar scenario as in the implementation of this test case) and therefore also the test suite run successfully through. Tested by myself. Cc: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-07sctp: Add RCU protection to assoc->transport_addr_listThomas Graf
peer.transport_addr_list is currently only protected by sk_sock which is inpractical to acquire for procfs dumping purposes. This patch adds RCU protection allowing for the procfs readers to enter RCU read-side critical sections. Modification of the list continues to be serialized via sk_lock. V2: Use list_del_rcu() in sctp_association_free() to be safe Skip transports marked dead when dumping for procfs Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Thomas Graf <tgraf@suug.ch> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-03sctp: Add support to per-association statistics via a new ↵Michele Baldessari
SCTP_GET_ASSOC_STATS call The current SCTP stack is lacking a mechanism to have per association statistics. This is an implementation modeled after OpenSolaris' SCTP_GET_ASSOC_STATS. Userspace part will follow on lksctp if/when there is a general ACK on this. V4: - Move ipackets++ before q->immediate.func() for consistency reasons - Move sctp_max_rto() at the end of sctp_transport_update_rto() to avoid returning bogus RTO values - return asoc->rto_min when max_obs_rto value has not changed V3: - Increase ictrlchunks in sctp_assoc_bh_rcv() as well - Move ipackets++ to sctp_inq_push() - return 0 when no rto updates took place since the last call V2: - Implement partial retrieval of stat struct to cope for future expansion - Kill the rtxpackets counter as it cannot be precise anyway - Rename outseqtsns to outofseqtsns to make it clearer that these are out of sequence unexpected TSNs - Move asoc->ipackets++ under a lock to avoid potential miscounts - Fold asoc->opackets++ into the already existing asoc check - Kill unneeded (q->asoc) test when increasing rtxchunks - Do not count octrlchunks if sending failed (SCTP_XMIT_OK != 0) - Don't count SHUTDOWNs as SACKs - Move SCTP_GET_ASSOC_STATS to the private space API - Adjust the len check in sctp_getsockopt_assoc_stats() to allow for future struct growth - Move association statistics in their own struct - Update idupchunks when we send a SACK with dup TSNs - return min_rto in max_rto when RTO has not changed. Also return the transport when max_rto last changed. Signed-off: Michele Baldessari <michele@acksyn.org> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-28sctp: Error in calculation of RTTvarSchoch Christian
The calculation of RTTVAR involves the subtraction of two unsigned numbers which may causes rollover and results in very high values of RTTVAR when RTT > SRTT. With this patch it is possible to set RTOmin = 1 to get the minimum of RTO at 4 times the clock granularity. Change Notes: v2) *Replaced abs() by abs64() and long by __s64, changed patch description. Signed-off-by: Christian Schoch <e0326715@student.tuwien.ac.at> CC: Vlad Yasevich <vyasevich@gmail.com> CC: Sridhar Samudrala <sri@us.ibm.com> CC: Neil Horman <nhorman@tuxdriver.com> CC: linux-sctp@vger.kernel.org Acked-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-14sctp: Make sysctl tunables per netEric W. Biederman
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-14sctp: Push struct net down into sctp_transport_initEric W. Biederman
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-22Merge branch 'kill_rtcache'David S. Miller
The ipv4 routing cache is non-deterministic, performance wise, and is subject to reasonably easy to launch denial of service attacks. The routing cache works great for well behaved traffic, and the world was a much friendlier place when the tradeoffs that led to the routing cache's design were considered. What it boils down to is that the performance of the routing cache is a product of the traffic patterns seen by a system rather than being a product of the contents of the routing tables. The former of which is controllable by external entitites. Even for "well behaved" legitimate traffic, high volume sites can see hit rates in the routing cache of only ~%10. The general flow of this patch series is that first the routing cache is removed. We build a completely new rtable entry every lookup request. Next we make some simplifications due to the fact that removing the routing cache causes several members of struct rtable to become no longer necessary. Then we need to make some amends such that we can legally cache pre-constructed routes in the FIB nexthops. Firstly, we need to invalidate routes which are hit with nexthop exceptions. Secondly we have to change the semantics of rt->rt_gateway such that zero means that the destination is on-link and non-zero otherwise. Now that the preparations are ready, we start caching precomputed routes in the FIB nexthops. Output and input routes need different kinds of care when determining if we can legally do such caching or not. The details are in the commit log messages for those changes. The patch series then winds down with some more struct rtable simplifications and other tidy ups that remove unnecessary overhead. On a SPARC-T3 output route lookups are ~876 cycles. Input route lookups are ~1169 cycles with rpfilter disabled, and about ~1468 cycles with rpfilter enabled. These measurements were taken with the kbench_mod test module in the net_test_tools GIT tree: git://git.kernel.org/pub/scm/linux/kernel/git/davem/net_test_tools.git That GIT tree also includes a udpflood tester tool and stresses route lookups on packet output. For example, on the same SPARC-T3 system we can run: time ./udpflood -l 10000000 10.2.2.11 with routing cache: real 1m21.955s user 0m6.530s sys 1m15.390s without routing cache: real 1m31.678s user 0m6.520s sys 1m25.140s Performance undoubtedly can easily be improved further. For example fib_table_lookup() performs a lot of excessive computations with all the masking and shifting, some of it conditionalized to deal with edge cases. Also, Eric's no-ref optimization for input route lookups can be re-instated for the FIB nexthop caching code path. I would be really pleased if someone would work on that. In fact anyone suitable motivated can just fire up perf on the loading of the test net_test_tools benchmark kernel module. I spend much of my time going: bash# perf record insmod ./kbench_mod.ko dst=172.30.42.22 src=74.128.0.1 iif=2 bash# perf report Thanks to helpful feedback from Joe Perches, Eric Dumazet, Ben Hutchings, and others. Signed-off-by: David S. Miller <davem@davemloft.net>